Puknace



Oct. 9,1923. Y 1,470,309

J. G. WIMMER FURNACE Filed Feb. 12, 1923 1 I- T? Ziwuanian:

/7' M kfo/m/ G. 27

Patented Get. 9, 1923.

JOHN G. WIMMER, OF LOCKPORT, ILLINOIS.

FURNACE.

Application filed February 12, 1923. Serial No. 618,465.

To all whom it may concern:

Be it known that I, JOHN G. l/VIMMER, a citizen of the United States, and a resident of Lockport, WVill County, Illinois, have invented certain new and useful Improvements in Furnaces, of which the following is declared to be a full, clear, and exact description.

This invention relates to furnaces, and its principal object is to provide an improved, smokeless furnace. Another object is to provide improved means for supplying preheated air to the combustion chamber, or fire pot of a furnace, to thereby improve combustion and as a consequence, eliminate smoke, increase the heat, and otherwise increase the efiiciency of operation of the furnace. Another object is to provide means for introducing pre-heated air to the combustion chamber or fire pot, and for increasing the velocity of the introduced heated air, to thereby increase the efficiency of operation. With these and other objects and advantages in view, this invention consists in the several novel features of construction, arrangement and combination of parts here inafter fully described and claimed.

The invention is clearly illustrated in the accompanying drawing, in which:

Fig. 1 is a View, partly in side elevation.

and partly in vertical section, of a furnace embodying one form of the present invention; Fig. 2 is a plan of one portionof the hot air conduit employed; F ig. 3 is a vertical, longitudinal section through said conduit and a fragment of thefurnace, and Fig. 4 is a front view of a certain door plate used in connection with the air conduit.

Referring to said drawing, which illusa trates one embodiment of the present invention, the reference character 10 designates a hot air furnace of common and well known construction, having the usual, casing 11 in which is contained the fire pot 12, the com 1 bustion chamber.

draught opening 18 controlled by cover 19 as usual. Leading from the dome 14 is the usual smoke stack 20, and leading from the casing are the air fines (not shown) for conducting the hot air to the places that are to be heated. Inasmuch as the furnace may be of any of the common and well known types of furnaces, no further detailed description thereof is necessary to the full understanding of the'present invention.

In the feed passage 16 is an air pre-heating conduit 21 which opens to the outer atmosphere and has a discharge end 22 directed into the combustion chamber 13,,and as a'preference, directed in a downwardly sloping direction toward the normal top of the bed of coal in the fire pot 12. Said air conduit, being exposed to the hot gases in the combustion chamber 13 and feed passage'16, it becomes heated thereby, and air passing through the conduit becomes heated before bein introduced into the combustion chamber. is a preference, the conduit 21 is located adjacent the top of the feed passage 16'so that it may not interfere with the work of shoveling coal into the furnace or raking down the fire and so forth. It is also placed at this location so as to receive the maximum heat from the fire in the furnace.

In order to obtain the best results the conduit 21 is divided into a number of narrow airpassages 23 separated by walls or partitions 24, whereby a maximum surface area of hot. conduit walls may be presented to the incoming air and the air may thereby be rapidly heated to a high degree of temperature before being discharged into the com- The walls or partitions 24 are shown as of Zigzag formation, and provide zigzag air passages in the conduit, which not only increase the length of the air passages but afford a greater surface area of metal for conducting heat to the passage Ways 23.

The conduit 21 has a cold air inlet opening 25 at one end, and a hot air discharge opening 26 at its other end. The inlet opening may open out directly through the front wall of the furnace if desired, but I have shown'said inlet opening in open communication with an air passage 27 formed in the fuel door 17. As shown, the fuel door has a channel like back plate 28 bolted, riveted or otherwise secured thereto, which plate extends up to the conduit 21 and has an opening 29 at its u per end which registers with the inlet opening of the conduit, vvhen the door is closed. Air enters through the draught opening in the fuel door, passes up through the air passage 27 in the door, and enters the conduit through its inlet 25, passes through the zigzag passages 23 in the conduit and is discharged toward the bed of coals in the fire pot.

e, For the purposeof increasing the velocity of the discharging pre-heated air, I have contracted the discharge end 22 and dischargeopening 26, by making the upper and lower walls 30, 31, at the discharge end of the conduitconverge toward each other, and as a preference the walls or partitions 24; are omitted between the converging upper and lower walls 30, 31. The result is that the velocity of the preheated air, as it discharges from the conduit, is increased, and enters thecombustion chamber in the form of a blast of air and supplies oxygen to the fuel at the place of consumption.

I The conduit may, in part, be formed by the top wall 33 of the fuel passage, and the bottom portion and partitions may be formed of a separate casting, bolted, riveted or otherwise securedto said top wall 33, or the conduit may be formed as an integral part of the top wall of the feed passage.

In operation, the cold air enters at the inlet end of the conduit, is pre-heated as it passes therethrough,and is discharged in p a generallydownwardly inclined direction toward the bed of co'als. From actual prac tice it has been found that the smoke is thoroughly consumed, a hotter fire is obtained, and that the hot burning gases enter the dome portion, thusproviding a heating chamber in the dome portion. Furthermore, smoke does not escape through the furnace door opening when the furnace door is opened, as is a customary occurrence even with the ordinary pre-heated air devices, but the pre-heated air stimulates the combustion and the products of combustion pass to, the smoke-stack.

While the invention has been illustrated and described in connection with. a hotair furnace, it is to be understood thatit is not intended to limit the invention thereto, as it is equally'applicable to steam boilers, hot water heaters and other heating plants, and while it is particularly useful in furnaces and other heating plants thatusc bituminouscoal as a fuel, itsadvantages are apparent when employed in plants that use anthracite coal as a fuel. By the termf1'1rnacs in the following claims, I desire to be understood as including all heating plants that employ bituminous or anthracite coal as a fuel.

More or less variation of the exact details of construction is possible without departing from the spirit of this invention; I desire, therefore, not to limit myself to the exact form of the construction shown and described, but intend, in the following claims, to point out all of the invention disclosed herein.

I claim as new and desire to secure by Letters Patent:

1. In a furnace, including its fire pot and a fuel feed passage leading thereto, a horizontally extending, wide and relatively shallow, air heating conduit located in said fuel passage, at the top thereof, and having a plurality of separate, independent air passages therein, each having individual inlet and outlet ports, there being a common cold air inlet passage, opening to all of said inlet ports, and a common hot air discharge passage into which all of said outlet ports 2. In a furnace, including its fire pot and a fuel feed passage leading thereto, a horizontally extending, wide and relatively shallow, air heating conduit located in said fuel passage, at the top thereof, and hav ing a plurality of separate, independent zigzag air passages therein, each having individual inlet and outlet ports,.and there being a common hot air discharge passage into which all of said outlet ports lead.

3. In a furnace, including its fire pot and a fuel feed passage leading thereto, a horizontally extending, wide and relatively shallow air heating conduit for supplying pre-heated air to the fuel, said conduit being located in the fuel feed passage adjacent its upper side, and being formed with spaced, upstanding partitions dividing said .conduit into a plurality of air passages,

each having individual inlet and outlet ports, there being a common cold air inlet passage opening to all of said inlet ports and there being a common hot air discharge passage into which all of said ports lead.

4. In a furnace, including its fire pot and a fuel feed passage leading thereto, a horizontally extending, wide and relatively shallow air heating conduit for supplying pre-heated air to the fuel, said conduit being located in the fuel feed passage adjacent its upper side, and being formed with zigzag, spaced, upstanding partitions divid ing said conduit into a plurality of zigzag air passages, each having individual inlet and outlet ports, there being a common cold air inlet passage opening to all of said inlet ports and there being a common hot air discharge passage into which all of said ports lead.

5. In a furnace having a fire pot, a fuel passage leading thereto, and a fuel door having an upright air passage provided with an air inlet at the front and an air outlet 5 at the top, a horizontal crosswise extending air heating conduit at the top of said fuel passage having an inlet opening adjacent JOHN G. WIMMER.

the outlet opening in the air passage of the door and having a discharge opening over the fire pot, there being separate air pas- 1 sages in said conduit and each having an individual inlet and outlet opening. 

